The Worcester Foundation's program in the study of normal and abnormal growth has as its objective the production of basic knowledge of animal cell structure and function with the ultimate aim of prevention or rational therapy of cancer. The program is an integrated investigation of cell surface properties, genome expression and tumor virology. In a number of instances our strengths in endocrine biology complement these studies. 1. Cell surface biology. Grant Fairbanks, Arthur Lomant: Phosphorylation of human erythrocyte membrane proteins; erythrocyte membrane pathophysiology in hemolytic disease; plasma membrane isolation and characterization. Robert Weihing: Actin and plasma membranes; adenovirus binding to microtubules. 2. Genome biology. Earl and Betty Baril: DNA synthesis regulation in normal and cancer cells; anti-tumor agents: mechanism of action on eukaryotic DNA synthesis. Jay Greenberg: Messenger ribonucleoproteins. Thoru Pederson: Ribonucleoprotein organization of heterogeneous nuclear and messenger RNA; structure and function of chromatin. 3. Tumor virology. Boyce Burge: Biological activity of envelope components of Sindbis virus; possible provirus state for lytic, single-stranded RNA virus. Ronald Luftig: Morphogenesis of murine leukemia viruses; development of techniques for the ultrastructural localization; packaging of DNA into the T4 capsid. Harvey Ozer: Expression of transformed phenotype in cell hybrids; temperature sensitive mutants of SV40 host cells; DNA replication in synchronized 3T3 cells.